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%I #8 Jul 22 2022 11:18:05
%S 198,3834,34434,230418,1327410,7005042,34949106,167809266,783885042,
%T 3587327730,16158854898,71878385394,316494986994,1381924896498,
%U 5991517716210,25821420060402,110707230375666,472515428744946,2008808357363442,8510221225819890
%N The Wiener index of the nanostar dendrimer defined pictorially as G(n) in the Darafsheh et al. reference.
%C a(2) has been checked by the direct computation of the Wiener index (using Maple).
%D M. R. Darafsheh, M. H. Khalifeh, Calculation of the Wiener, Szeged, and PI indices of a certain nanostar dendrimer, Ars Comb., 100, 2011, 289-298.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (11,-42,64,-32).
%F a(n) = 4^n*(1728*n - 1872) + 2340*2^n -270.
%F G.f.: 18*(11+4*x)*(1+8*x)/((1-x)*(1-2*x)*(1-4*x)^2).
%p a := proc (n) options operator, arrow: 4^n*(1728*n-1872)+2340*2^n-270 end proc: seq(a(n), n = 0 .. 22);
%Y Cf. A227706.
%K nonn,easy
%O 0,1
%A _Emeric Deutsch_, Jul 29 2013